I need a little help with this script...

I'm scripting my very first magic wand and im having trouble with it. Here is the script:

showoffense()
{
key av = llDetectedKey(0);
string message = "Choose an offense spell!";
list buttons = ["Flippindo", "Argnus", "Traparsk", "Leviosa", "Leviosa Maximus"];
integer channel = -1337;
llDialog(av, message, buttons, channel);
}

showdefense()
{
key av = llDetectedKey(0);
string message = "Choose a defense spell!";
list buttons = ["Protecto", "Repulso", "Expecto Potronum", "Cloak", "Astral Projectum"];
integer channel = -1337;
llDialog(av, message, buttons, channel);
}

showmisc()
{
key av = llDetectedKey(0);
string message = "Choose an misc spell!";
list buttons = ["Lumos", "Accio", "---"];
integer channel = -1337;
llDialog(av, message, buttons, channel);
}

default
{
state_entry()
{
llSay(0, "If you need help with the usage of this staff, please read the notecard that came with it.";
llListen(-1337, "", NULL_KEY, "";
}

touch_start(integer total_number)
{
key av = llDetectedKey(0);
llSay(0, "Choose a Spell to Inflict upon your friends and foes!";
string message = "Choose what type of spell";
list buttons = ["Offense", "Defense", "Misc"];
integer channel = -1337;
llDialog(av, message, buttons, channel);
}

listen( integer channel, string name, key id, string message )
{
if(message == "Offense"
{
showoffense();
}
}
}

When I click the wand, the first menu comes up, when I click offense, it doesnt come up. The script compiles perfectly.

llDetectedKey is only valid in the Touch function.
Try this:

key av;

showoffense()
{
	string message = "Choose an offense spell!";
	list buttons = ["Flippindo", "Argnus", "Traparsk", "Leviosa", "Leviosa Maximus"];
	integer channel = -1337;
	llDialog(av, message, buttons, channel);
}

showdefense()
{
	string message = "Choose a defense spell!";
	list buttons = ["Protecto", "Repulso", "Expecto Potronum", "Cloak", "Astral Projectum"];
	integer channel = -1337;
	llDialog(av, message, buttons, channel);
}

showmisc()
{
	string message = "Choose an misc spell!";
	list buttons = ["Lumos", "Accio", "---"];
	integer channel = -1337;
	llDialog(av, message, buttons, channel);
}

default
{
	state_entry()
	{
		llSay(0, "If you need help with the usage of this staff, please read the notecard that came with it.");
		llListen(-1337, "", NULL_KEY, "");
	}

	touch_start(integer total_number)
	{
		av = llDetectedKey(0);
		llSay(0, "Choose a Spell to Inflict upon your friends and foes!");
		string message = "Choose what type of spell";
		list buttons = ["Offense", "Defense", "Misc"];
		integer channel = -1337;
		llDialog(av, message, buttons, channel);
	}

	listen( integer channel, string name, key id, string message )
	{
		if(message == "Offense")
		{
			showoffense();
		}
	}
}

thank you!!!